The subject matter herein relates generally to solar junction boxes for solar panels.
Photovoltaic (PV) modules or arrays, such as solar panels, produce electricity from solar energy. Electrical power produced by PV modules reduces the amount of energy required from non-renewable resources such as fossil fuels and nuclear energy. Significant environmental benefits are also realized from solar energy production, for example, reduction in air pollution from burning fossil fuels, reduction in water and land use from power generation plants, and reduction in the storage of waste byproducts. Solar energy produces no noise, and has few moving components. Because of their reliability, PV modules also reduce the cost of residential and commercial power to consumers.
PV cells are essentially large-area semiconductor diodes. Due to the photovoltaic effect, the energy of photons is converted into electrical power within a PV cell when the PV cell is irradiated by a light source such as sunlight. PV cells are typically interconnected into solar modules that have power ranges of up to 100 watts or greater. For large PV systems, special PV modules are produced with typical power range of up to several 100 W. A photovoltaic module is the basic element of a photovoltaic power generation system. A PV module has many solar cells interconnected in series or parallel, according to the desired voltage and current parameters. PV cells are connected in series with thin contacts, such as a foil. The foil is terminated to a junction box, which may electrically connect groups of the PV cells and/or solar panels.
The junction box is typically connected to the back side of the solar panel, such as to a backsheet. The foil is terminated to a corresponding terminal in the junction box. Typically, the foil is connected to the terminal via a mechanical spring clip. The spring clips can lose their mechanical properties, such as in the elevated temperature environment of the solar application. Other known solar junction boxes have terminals that are soldered or welded to the foil. However, the soldering process can be slow and tedious and the welding process requires special equipment to weld the foil to the terminal. Additionally, the foils may be routed in various different directions relative to the solar panel, such as side-to-side, top-to-bottom, bottom-to-top, and the like. The junction box must be oriented in a direction that corresponds to the foil axis direction of the foil for proper termination to the terminal because the terminal is limited to receiving the foil in a single direction. Conventional solar junction boxes only accept the foil from one direction. A need remains for a solar junction box capable of overcoming the shortcomings of conventional solar junction boxes.